Copyright laws protect original expressions including performances captured in audio and visual form. The proliferation of digital technology, such as computers and the internet, has introduced a myriad of challenges to rights holders, since the use of digital technology allows for exact copies of media to be made without degradation. For instance, an image obtained using a capture device such as a digital still camera or digital video camera may be copied an infinite number of times by a theoretically infinite number of persons. If any such copying is unauthorized, rights holders may have legal recourse, but may face tremendous difficulty in tracing and proving the extent of such unauthorized copying.
The proliferation of digital technology also affects rights holders with respect to live performances. For instance, the ever-increasing ubiquity of digital cameras creates a point of conflict for rights holders, such as performers or venue management authorities. Specifically, concert goers are accustomed to taking digital photographs of themselves and their surroundings using digital cameras and the like. However, in a concert setting, such cameras could be used to capture content which is owned by, e.g., the performer. Therefore, generally speaking, most venues and performers prohibit attendees at a performance from even bringing a content capture device such as a digital camera into the venue. Even if the venue or performer wished to grant the attendee a limited right to use his capture device, due to the innate nature of digital content, the venue or performer would have no guarantee that the attendees would honor any such limits.
In response to the challenges posed by the proliferation of digital content capture and management devices, various digital rights management (DRM) schemes and techniques have been developed. For example, different DRM implementations include, but are not limited to, Microsoft Windows Media DRM, Open Mobile Alliance DRM, Open MG (Sony), Fair Play (i.e. Apple iTunes), and the MPEG 21 rights expression language and rights data dictionary. These and other DRM implementations may be used to render content in a DRM-compatible format. However, rendering content in a DRM-compatible form may require additional steps and coordination that content owners may wish to avoid in certain circumstances.
Another known technique used in the field of content protection is watermarking. Watermarking comprises placing additional data in the same bits comprising content data. Various watermarking schemes have been proposed in which the watermark does not noticeably degrade the quality of the content when present. Furthermore, such watermarking schemes may be implemented in a manner that the quality of the content is severely degraded if the watermark is removed.
The use of watermarks in the context of identifying digital rights has been disclosed. For example, U.S. Patent Application Publication No. 2005/0286736 (Rhoads) includes discussion of the use of a database registry from which the identity of a rights holder for a copyrighted work may be ascertained by decoding information placed in the content by the rights holder. For instance, at a concert, audio may be identification coded before it drives concert hall speakers with the result that unauthorized recordings of the concert can be traced to a particular place and time.
It would be desirable for a venue or other rights holder to be able to implement a DRM policy or DRM policies with regard to content that is captured by third parties unaffiliated with the rights holder, such as concert attendees, without the need for the rights holder to resort to watermarking or otherwise including data in the content. Furthermore, it would be desirable to track content to a particular source in the event of a violation of DRM policies, or for other purposes.